1. Field of the Invention
This invention relates to an exothermic body, and more particularly to an elastic, soft and flexible exothermic body having its core of a foamed plastic covered with an air-permeable thin film, cells of the foamed plastic being filled with a chemical heat generating agent or exothermic agent (hereinafter, referred to exothermic agent).
2. Description of the Prior Art
It is very uncomfortable to wear cold shoes for a long time in a cold environment, and it may also cause a disease. There has been, however, no effective warming insole in order to prevent such discomfort.
On the other hand, arthritic, neuralgic or rheumatic patients and the like feel an acute pain in their affected parts of their body in winter, so that they suffer from a serious pain. In this respect, it is necessary to warm up these affected parts in order to abate such pain. However, there has never been a suitable warming implement for simply and easily warming up such affected parts which are either severly bent and moved as in a joint and the like, or extending over a wide area.
A lot of simple, safety and energy-conservation type warming implements utilizing an exothermic agent have recently been employed in place of warming implements utilizing methanol and benzine as well as pulverized coal etc. as fuels, and another type of warming implements in which a battery is used. In such energy-conservation type warming implement, heat is generated by reacting, with oxygen, exothermic agent being a mixture of an easily oxidizable material such as iron power or sodium sulfide, carbon as a catalyst, and saline solution as an oxidation accelerator.
In such type of warming implement, however, the exothermic agent is contained in a bag in a powdery or slurry form, and in addition, a volume of the bag is considerably larger than that of the exothermic agent to facilitate a contact with oxygen. Accordingly, the exothermic agent freely transfers in the bag in accordance with deformation, transference and reversal or the like of the warming implement, so that the agent is unevenly distributed in the bag and the distribution of exothermic heat becomes uneven in the entire warming implement. Further, when such warming implement is pressed, the agent does not sufficiently contact with oxygen because of lack of breathability, thereby generating insufficient heat, or when the implement becomes solid, such implement does not generate heat any more, even if such pressure is removed after the implement was once made to be solid. For these reasons, satisfactorily warming implements have never been proposed heretofore.